Heart rate is a speed of heart beat measured by number of poundings of the heart per unit of time. Typically, the heart rate is measured in Beats per Minute (BPM). The heart rate may vary according to body of an individual, including absorption of oxygen and excretion of carbon dioxide. Heart rate variability (HRV) is a physiological phenomenon of variation in a time interval between the heartbeats. Typically, the HRV may be measured by the variation in the beat-to-beat interval.
There exist solutions to determine heart rate and heart rate variability (HRV) of the individual using an electronic device. Typically, the existing solutions use a concept of photoplethysmography or ECG to determine heart rate and heart rate variability (HRV). Generally, the photoplethysmography is well suited for determining the heart rate, however fails to determine the HRV accurately due to low temporal resolution. Another solution offered is use of a digital stethoscope to capture the heartbeat sounds for extracting the heart rate and HRV of the individual. In spite of providing high temporal resolution (44.1 kHz sampling rate), the solution is susceptible to mechanical friction, ambient sounds, audio feedback and noise is generated by the electronic circuits. In order to eliminate the noise, noise cancellation technique is used by applying a low-pass filter on an audio signal. However, the noise cancellation technique cannot eliminate the noise components present in the pass band. Therefore, frequency domain representation often fails to detect the heart rate accurately due to abrupt change in dominant peak location.